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Nanostructured Morphologies In Glassy Polymer Networks, Brian Greenhoe 2016 University of Southern Mississippi

Nanostructured Morphologies In Glassy Polymer Networks, Brian Greenhoe

Dissertations

The body of this work describes a novel approach for the dispersion of multi-walled carbon nanotubes in a high Tg epoxy prepolymer matrix using a twin screw high-shear continuous reactor. The method demonstrated improves on previous dispersion methods in several ways. It offers increased efficiency through excellent heat transfer, while being solvent-less, scale-able, and tailorable to drive dispersion states to judiciously chosen dispersion states. Furthermore, it was shown that dispersion state and agglomerate morphology can be directed, in several ways, through processing conditions and also by controlling the matrix viscosity profile through cure. Broadband dielectric spectroscopy, optical hot-stage microscopy ...


Simulation Investigation Of Temperature Distribution In Large Aluminium Panel During Autoclave Age Forming Process, Yongqian Xu 2016 Central South University

Simulation Investigation Of Temperature Distribution In Large Aluminium Panel During Autoclave Age Forming Process, Yongqian Xu

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.


Multi-Dome Forming Of A Ti–Al–Mn Alloy, Sergey Aksenov, Aleksey Kolesnikov, Ivan Zakhariev 2016 National Research University Higher School of Economics

Multi-Dome Forming Of A Ti–Al–Mn Alloy, Sergey Aksenov, Aleksey Kolesnikov, Ivan Zakhariev

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.


Synthetic Defects For Vibrothermography, Jeremy Blake Renshaw, Stephen D. Holland, R. Bruce Thompson, David J. Eisenmann 2016 Iowa State University

Synthetic Defects For Vibrothermography, Jeremy Blake Renshaw, Stephen D. Holland, R. Bruce Thompson, David J. Eisenmann

David Eisenmann

Synthetic defects are an important tool used for characterizing the performance of nondestructive evaluation techniques. Viscous material‐filled synthetic defects were developed for use in vibrothermography (also known as sonic IR) as a tool to improve inspection accuracy and reliability. This paper describes how the heat‐generation response of these VMF synthetic defects is similar to the response of real defects. It also shows how VMF defects can be applied to improve inspection accuracy for complex industrial parts and presents a study of their application in an aircraft engine stator vane.


Quantification Of Toolmarks, L. Scott Chumbley, David J. Eisenmann, M. Morris, S. Zhang, J. Kreiser, J. Craft, C. Fisher 2016 Iowa State University

Quantification Of Toolmarks, L. Scott Chumbley, David J. Eisenmann, M. Morris, S. Zhang, J. Kreiser, J. Craft, C. Fisher

David Eisenmann

No abstract provided.


Forensic Examination Using A Nondestructive Evaluation Method For Surface Metrology, David J. Eisenmann, L. Scott Chumbley 2016 Iowa State University

Forensic Examination Using A Nondestructive Evaluation Method For Surface Metrology, David J. Eisenmann, L. Scott Chumbley

David Eisenmann

The objective of this paper is to describe the use of a new technique of optical profilometry in a nondestructive, non‐contact fashion for the comparison of two metallic surfaces, one hard and one soft. When brought in contact with one another, the harder material (i.e. the tool) will impress its surface roughness onto the softer. It is understood that the resulting set of impressions left from a tool tip act in a manner similar to a photographic negative, in that it leaves a reverse, or negative impression on the surface of a plate. If properly inverted and reversed ...


Flourescent Penetrant Inspection—Cleaning Study Update, David J. Eisenmann, Lisa H. Brasche 2016 Iowa State University

Flourescent Penetrant Inspection—Cleaning Study Update, David J. Eisenmann, Lisa H. Brasche

David Eisenmann

Fluorescent penetrant inspection (FPI) is widely used in the aviation industry and other industries for surface‐breaking crack detection. As with all inspection methods, adherence to the process parameters is critical to the successful detection of defects. There is variety of lubricants and surface coatings used in the aviation industry which must be removed prior to FPI. Before the FPI process begins, components are cleaned using a variety of cleaning methods which are selected based on the alloy and the soil types which must be removed. It is also important that the cleaning process not adversely affect the FPI process ...


From Xst To F-117a, Alan Brown 2016 Embry-Riddle Aeronautical University

From Xst To F-117a, Alan Brown

ERAU Prescott Aviation History Program

Learn the remarkable story of stealth technology from the man often referred to as “Mr. Stealth.” From 1975-1989 Alan Brown was a member of Lockheed “Skunk Works”, becoming program manager & chief engineer for the F-117A Stealth Fighter from initial concept until the first production aircraft was built, 1978 to 1982. Hear the inside story of the many challenges faced by the stealth program and how they were solved.


Metamodels Of Residual Stress Buildup For Machining Process Modeling, Stuart B. McCrorie, Michael Sangid 2016 Purdue University

Metamodels Of Residual Stress Buildup For Machining Process Modeling, Stuart B. Mccrorie, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the process of machining materials, stresses, called residual stresses, accumulate in the workpiece being machined that remain after the process is completed. These residual stresses can affect the properties of the material or cause part distortion, and it is important that they be calculated to prevent complications from arising due to the residual stresses. However, these calculations can be incredibly computationally intensive, and thus other methods are needed to predict the residual stresses in materials for quick decision-making during machining. By using metamodels - a method of representing data where few data points exist - we can achieve an accurate prediction ...


Evaluation Of Strain Distortion Correction Protocol Using Scanning Electron Microscopy And Digital Image Correlation, Alexandra Mallory, Alberto Mello, Michael Sangid 2016 San Diego State University

Evaluation Of Strain Distortion Correction Protocol Using Scanning Electron Microscopy And Digital Image Correlation, Alexandra Mallory, Alberto Mello, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

Scanning electron microscopy in combination with digital image correlation (SEM-DIC) is a useful technique for measuring strain in materials at the micro-scale. In particular, it can be used to identify micro-scale strain localizations that are the precursor to material failure. While SEM produces high resolution images of the microstructure, the images also contain a large amount of distortion that, during DIC, will result in distorted strain values that require correction. In this project, a nickel-based alloy underwent cyclic mechanical fatigue at three different high temperatures to a targeted maximum strain. Scanning electron microscopy imaging was done on a 200x150μm area ...


Statistical Impact-Echo Analysis Using Bag-Of-Echoes Model For Concrete.Pdf, Jiaxing Ye 2016 National Institute of Advanced Industrial Science and Technology

Statistical Impact-Echo Analysis Using Bag-Of-Echoes Model For Concrete.Pdf, Jiaxing Ye

Jacky Yin

In recent years, advancement in information technologies, i.e. cloud service and high speed wireless network, greatly facilitate the large collection of structural health monitoring (SHM) data. In order to effectively exploit massive sensor data for accurate condition assessment of infrastructures, there has been increasing interest in application of statistical pattern recognition methods in the field of SHM. This paper addresses development of efficient pattern analysis scheme for impact-echo test, which is one of the most conventional nondestructive test (NDT) methods. The proposed scheme stems from Bag-of-feature (BoF) model, which has been successfully applied for natural language processing and computer ...


Statistical Impact-Echo Analysis Using Bag-Of-Echoes Model For Concrete.Pdf, Jacky Yin 2016 Hongkong Baptist university

Statistical Impact-Echo Analysis Using Bag-Of-Echoes Model For Concrete.Pdf, Jacky Yin

Jacky Yin

In recent years, advancement in information technologies, i.e. cloud service and high speed wireless network, greatly facilitate the large collection of structural health monitoring (SHM) data. In order to effectively exploit massive sensor data for accurate condition assessment of infrastructures, there has been increasing interest in application of statistical pattern recognition methods in the field of SHM. This paper addresses development of efficient pattern analysis scheme for impact-echo test, which is one of the most conventional nondestructive test (NDT) methods. The proposed scheme stems from Bag-of-feature (BoF) model, which has been successfully applied for natural language processing and computer ...


Predicting Flexural Strength Of Composite Honeycomb Core Sandwich Panels Using Mechanical Models Of Face Sheet Compressive Strength, Nicholas Bruffey, William Shiu 2016 California Polytechnic State University, San Luis Obispo

Predicting Flexural Strength Of Composite Honeycomb Core Sandwich Panels Using Mechanical Models Of Face Sheet Compressive Strength, Nicholas Bruffey, William Shiu

Materials Engineering

The design process at Zodiac Aerospace requires the ability to accurately predict the strength of a composite honeycomb core sandwich panel to adhere to strict FAA regulations. The most common failure mode in long beam composites is in compression. Following ASTM D7249 for a four-point bend test of a long beam flexural test, a mechanical model has been developed that relates the compressive strength of glass fiber face sheets to the flexural strength of the sandwich panel. Zodiac does not currently have data on the compressive strength of the face sheets, so testing was performed to find this property. Asymmetric ...


Effects Of Curing Cycle And Loading Rates On The Bearing Stress Of Double Shear Composite Joints, Mateja Andrejic 2016 California Polytechnic State University - San Luis Obispo

Effects Of Curing Cycle And Loading Rates On The Bearing Stress Of Double Shear Composite Joints, Mateja Andrejic

Master's Theses and Project Reports

In the last few decades, there has been a shift to using more lightweight materials for the potential of fuel consumption reduction. In the Aerospace Industry, conventional metal structures are being replaced by advanced composite structures. The major advantage of an advanced composite structure is the huge reduction in the number of parts and joints required. Also composite materials provide better resistance to creep, corrosion, and fatigue. However, one cannot eliminate all the joints and attachments in an aircraft’s structure. Eliminating structural joints is impractical in present-day aircraft because of the requirements for inspection, manufacturing breaks, assembly and equipment ...


Implementation Of A Large Solar Collector For Solar Light Energy, Skye Leake, Thomas McGuire, Michael Hirsch, Michael Parsons, Jeremy Straub, Scott Kerlin 2016 Selected Works

Implementation Of A Large Solar Collector For Solar Light Energy, Skye Leake, Thomas Mcguire, Michael Hirsch, Michael Parsons, Jeremy Straub, Scott Kerlin

Jeremy Straub

The challenge of providing large amounts of electrical energy for spacecraft over the course of long du-ration missions has long been an area of aerospace research. This need is particularly pronounced for a solar-powered in-space 3D printer [1]. Solar flux is commonly collected with solar panels for powering spacecraft. This is a reliable and safe method for electricity generation. Other generation methods, such as onboard nuclear power, present safety concerns.
Large solar collectors also have other benefits over alternate electricity generation methods. Theses benefits include using the solar collector as a solar shade, and using the back side of the ...


Origami Style Solar Panels With Development Of Dual Purpose Integrated Phased Array Communications System, Alexander Holland, Wilson Lysford, Jens Pearson, Jeremy Straub, Scott Kerlin 2016 Selected Works

Origami Style Solar Panels With Development Of Dual Purpose Integrated Phased Array Communications System, Alexander Holland, Wilson Lysford, Jens Pearson, Jeremy Straub, Scott Kerlin

Jeremy Straub

The purpose of this poster is to explore space based power generation capabilities and transmission based on using Origami Style Solar and Antenna Panels (OSSAP). Basically, the OSSAP is designed to be a new type of origami panels that operate differently from conventional solar panels and antennas. They should be easier to manufacture and usable on a wide range of spacecraft. They have a lower launch volume and mass; however, once in space the system unfolds to provide a large surface area. The unfolding can be done in several ways including using a pressurized gas system for deployment. This method ...


In-Space 3d Printing Scientific Remote Sensing Missions, Michael Hirsch, Thomas McGuire, Skye Leake, Michael Parsons, Jeremy Straub, Scott Kerlin 2016 Selected Works

In-Space 3d Printing Scientific Remote Sensing Missions, Michael Hirsch, Thomas Mcguire, Skye Leake, Michael Parsons, Jeremy Straub, Scott Kerlin

Jeremy Straub

Currently, remote sensing missions involve the pro-duction of complex and deployable structures that must withstand the forces involved with launching and assembly in space. To combat this, the technology of 3D printing [1] can be applied. Additive manufacturing technology has improved greatly in the recent past, al-lowing for the possibility of in-space 3D printing [2].
By taking the concepts of 3D printing and using them for scientific remote sensing missions [3], it is possible to print structures that would be otherwise impossible, due to constraints for terrestrial construc-tion, launch and deployment. A design is proposed in [2] that will both ...


National Defense 3d Space Printing, Michael Parsons, Thomas McGuire, Michael Hirsch, Skye Leake, Jeremy Straub, Scott Kerlin 2016 Selected Works

National Defense 3d Space Printing, Michael Parsons, Thomas Mcguire, Michael Hirsch, Skye Leake, Jeremy Straub, Scott Kerlin

Jeremy Straub

National defense is a strategic priority that is challenged everyday. A variety of humans and systems protect the United States from global terrorism. Space-craft are key components of the national defense. They provide surveillance, communications and navigation and other services.
These craft can be augmented using in-space 3D printing. An in-space 3D printer could be used for applications relevant to attacking or defending spacecraft or terrestrial targets. Currently, weapons must be launched from the ground. A weapon can be launched from an ideal point in orbit, on the other, hand, enjoys a variety of benefits. This poster considers how in-space ...


Design For An In-Space 3d Printer, Thomas McGuire, Michael Hirsch, Michael Parsons, Skye Leake, Jeremy Straub, Scott Kerlin 2016 Selected Works

Design For An In-Space 3d Printer, Thomas Mcguire, Michael Hirsch, Michael Parsons, Skye Leake, Jeremy Straub, Scott Kerlin

Jeremy Straub

Getting into space is a key constraint of current space mission designs. Launching spacecraft or components for spacecraft into space requires large amounts of structural components and packaging to secure it, adding additional mass and cost to the launch. Being able to bypass this current system would allow more frequent and cheaper space missions. An in space 3D printer is key to this. By placing a 3D printer in orbit, raw material (which requires less support and packaging to ship) can be sent to space. Craft and components can be fabricated on demand. This also allows craft to be designed ...


Effect Of Low Velocity Impact On The Vibrational Behavior Of A Composite Wing, Richard M. de Luna 2016 California Polytechnic State University, San Luis Obispo

Effect Of Low Velocity Impact On The Vibrational Behavior Of A Composite Wing, Richard M. De Luna

Master's Theses and Project Reports

Impact strength is one of the most important structural properties for a designer to consider, but it is often the most difficult to quantify or measure. A major concern for composite structures in the field is the effect of foreign objects striking composites because the damage is often undetectable by visual inspection. The objective for this study was to determine the effectiveness of using dynamic testing to identify the existence of damage in a small scale composite wing design. Four different impact locations were tested with three specimens per location for a total of 12 wings manufactured. The different impact ...


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